<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/vue/2.6.5/vue.min.js"></script>
</head>

<style>
    .wrapper {
        width: 200px;
        height: 200px;
        background-color: red;
        border-radius: 50%;
        position: relative;
        overflow: hidden;
    }

    .wrapper>div {  
        width: 100%;
        height: 100%;
        position: absolute;
        top: 0;
        left: 0;
    }

    .item1{
        background-color: aqua;
    }

    .item2{
        background-color: brown;
        transform: rotate(45deg);
    }
</style>

<body>
    <div id="app">
        <div class="wrapper">
            <div class="item1">1</div>
            <div class="item2">2</div>
        </div>
    </div>
</body>

<script>
    new Vue({
        el: "#app"
    })
</script>

</html>